KR20000025939A - Structure of gateway for interlocking web and database and interlocking method g using the same - Google Patents

Abstract

PURPOSE: A structure of a gateway for interlocking a web and a database and an interlocking method using the same are provided to complement service capability of the web and an OODBMS(Object Oriented DataBase Management System) each other, and integrate the ability and the OODBMS. CONSTITUTION: A structure of a gateway for interlocking a web and a database comprises: a gateway for transmitting a request from a client to a message Q, and receiving the result through a web server; a monitor for generating application servers by referring to a parameter related to a system environment, for processing a broadcast message and a transaction message among transmitted messages from the gateway, for informing the result to the gateway, for eliminating an abnormal application server by observing whether the application servers exist, and replacing as a new application server; and the application servers for processing by receiving one message in one time about a message except the transaction message and the broadcast message, and for informing the result to the gateway. The gateway supports a database manager command and a gateway command such as a table 2(classes, attributes, methods, indexes, privileges, objects, questions, transactions, user managements).

Description

Gateway structure for interworking web and database and interworking method

The present invention relates to a structure of a gateway for interworking a web and a database, and an interworking method using the same. Particularly, the present invention relates to a web that complements and integrates a web service capability and an object-oriented database management system (OODBMS). The present invention relates to a structure of a gateway for interworking with a database and an interworking method using the same.

The web provides a common client called a browser and operates with a hypertext-based user interface and standards such as HTML, CGI, and HTTP. However, due to the weakness of data access and the inability to provide various queries, it is not easy to transmit and express data on a large scale internet-based hypermedia information system. Database management systems, on the other hand, provide various functions for organizing and managing a lot of data. Therefore, from the information service point of view, one of the best ways to develop a large data service system is to integrate the useful functions of the database management system with the service capabilities of the Web in complementary terms. The key to this integration is the database gateway. However, the conventional gateway architecture has caused a lot of problems in performance due to a significant burden on the web server when connecting the web and the database management system.

Conventional database gateway research has divided database gateways into various categories with an emphasis on where the access to the database takes place, and the database can be accessed from the server side or the client side. In other words, by extending the server or client, you can integrate the database management system with the Web.

When extending to the server side, the database gateway can be made using CGI or API. The use of CGI involves firstly the CGI executable structure, in which the database gateway itself is executable, and secondly, the CGI application server architecture in which the CGI processor simply passes the client's database requests to separate data application servers. Can be broken down. When extending to the client side, the database management system can be accessed directly by extending the browser or using an external viewer such as an MPEG player.

In the CGI executable architecture, integration with the Web and database management systems is straightforward and straightforward because database gateways can be implemented in a typical development environment on the Web or database. This structure does not require any improvements to the web server or browser. The server makes each database request to the database gateway processor and then connects the database management system through the processor that received the request. The server terminates the gateway process after receiving the result of the request from the processor that received the request. This architecture can lead to significant performance degradation due to system resource constraints, the communication between the web server and the database gateway, and the cost of processor creation in large service environments that must simultaneously handle many requests to the database management system.

In the CG1 application server architecture, the database gateway is divided into two modules: the gateway for sending requests and the application server for handling requests. The module that sends the request can execute CGI so that when the client receives a database request, it forwards the request to the appropriate application server. Application server modules typically act as daemon processors that connect to the database and wait for requests. The number of application server processors is determined by considering available system resources. However, there is a problem in that a separate cost caused by interprocessor communication occurs.

In the case of extending the web browser, the script and function of the database service and the database service function are included in the web browser to serve the web and the database as one integrated environment. This interworking is accomplished by adding a database path through which a database engine can be directly connected instead of a conventional web server.

In the case of using an external viewer, the web application can be used through a plug-in method supported by the web. In this case, it is possible to connect users and database management systems more effectively by using a browser dedicated to the database, but it is impossible to apply a standardized web interface because the database service is provided through the protocol of the database itself without using HTTP protocol and HTML. There is a problem.

Netscape's NSAPI and Internet Information Server's ISAPI provide an extensible API that allows users to extend the capabilities of their Web server. Therefore, the database gateway can be implemented with an extensible API that dynamically connects to the web server process. This reduces the cost of processor management in CGI. However, in this architecture, the implementation of the database gateway depends on the API of the specific web server.

Therefore, the present invention adopts the CGI application server structure, drives the database application server and the monitor as a daemon processor, and the structure of the gateway for interworking the web and the database so that the database, the web, and the gateway have an independent structure, and the interworking using the same. The purpose is to provide a method.

The gateway for interworking with the web and the database according to the present invention for achieving the above object is to send a request from the client to the message queue to receive a result of the request to the web server and the parameters related to the system environment Creates an application server, processes transaction messages and broadcast messages among the messages transmitted from the gateway, notifies the gateway of the result, and monitors the abnormality of the application server to remove the abnormal application server, and to a new application server. And an application server for receiving and processing one message at a time for a message other than a transaction message and a broadcast message among the messages transmitted from the gateway, and notifying the gateway of the result. The features.

In addition, the web and database interworking method using a gateway according to the present invention for achieving the above object comprises the steps of the gateway receiving a database request from a web client to load the request of the web client in a message queue, Distinguishing and receiving the loaded client's request according to the type of the monitor and the application server; and analyzing the message received from the message queue, when the message loaded in the message queue is a transaction message or a broadcast message. Processing this in a monitor; analyzing a message received from the message queue; processing a message other than a transaction message or a broadcast message by an application server; and processing a request processed by the monitor and the application server. Archive to file And notifying the gateway by using the signal that the request processing is completed, and transmitting the request processing result to the web server by the gateway that has received the request processing result and the request processing completion signal from the monitor and the application server. Characterized in that made.

1 is a functional block diagram illustrating a connection environment between a web and a database to which the present invention is applied.

2 is a flowchart illustrating a web and database interworking method using a gateway according to the present invention.

<Description of the symbols for the main parts of the drawings>

11: gateway 12: monitor

13: application server 14: message queue

15: TCL file 16: DBMS

17: DBMS server

From an information service perspective, one of the best ways to develop a large data service system is to combine the useful features of a database management system with the service capabilities of the Web in a complementary way. To this end, the gateway according to the present invention adopts an application server structure based on CGI. In other words, to avoid the burden of modification caused by the rapidly growing web and communication protocols, and to develop a database gateway using a standardized API and connect naturally to the current web server, It supports both GET and POST methods.

In this CGI application server architecture, the application server and monitor that make up the application server module act as daemon processors. If the same application accessing a single database needs to be run for every request from a client, connecting to the database management system can cause performance overhead due to processor creation and destruction. This overhead can be minimized by running database application servers and monitors as daemon processors. That is, an application server that exists in an executable state is waiting for a request from a client, and a monitor manages normal operation on a database management system, a web server, and a gateway.

In addition, the present invention proposes an independent structure of a database, a web, and a gateway. Conventional gateways are not portable and scalable because they are database dependent. The present invention proposes a gateway interworking with the database and the web, and the monitor, gateway structure, and application server configuring the gateway have an independent structure that is separated as much as possible. And since the application server that sends and receives data directly to and from the database management system is also modular, it can be linked with various databases by adding only basic modules.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

1 is a functional block diagram illustrating a web and database connection environment to which the present invention is applied, and FIG. 2 is a flowchart illustrating a web and database interworking method using a gateway according to the present invention.

The gateway 10 according to the present invention is a CGI application server method, and is composed of a gateway 11, a monitor 12, and an application server 13. The gateway 10 of the CGI application server structure is divided into two modules, a request sending part and an application server processing a request. The sending module is a CGI executable part. To communicate the request. The application server 13 module also operates as a daemon processor that connects to the database and waits for requests. The monitor 12 also operates as a daemon processor. In the present invention, the gateway 11 operates as a CGI executable module.

The gateway 11, the monitor 12 and the application server 13 share one message queue 14. Upon receiving the database request from the web client (21), the gateway 11 loads the request of the web client to the message queue 14 (22). Thereafter, the gateway 11 distinguishes its own message according to the request and receives it from the monitor 12 and the application server 13, and the database 16 results from the application server 13 through the database management system server 17. Wait for The monitor 12 and the application server 13 analyze the message sent to it from the message queue 14, and if the message loaded in the message queue 14 is a transaction message or a broadcast message, it monitors the message at the monitor 12. Process (25). The monitor 12 is generated when the gateway starts to operate. The monitor 12 generates the application server 13 by referring to parameters related to the system environment such as the name and number of application servers, a path to the server, and waits for a message from the gateway while running in an infinite loop. In addition, the monitor 12 monitors an abnormality of the application server, and removes the abnormal application server and replaces it with a new application server. When the processing of the transaction message or the broadcast message is completed, the monitor 12 needs to transmit a result of the request to the gateway 11, and in most cases, a large amount of data makes it more efficient to use a file than a message. Therefore, the request processing result is stored in the determined file and notified to the gateway 11 using a signal that the processing is completed (26). If the message is analyzed and it is a message other than a transaction message or broadcast message, the message is processed by the application server 13 (24). The application server 13 is not only an application of the database management system but also a server of the gateway 11. Each application server 13 actively processes the request. That is, the message given to the self should be accepted one message at a time from the message queue 14 to process the request, record the processing result of the request at a specific location, and notify the gateway 11 of the completion of the request processing. . The request processing result is stored in HTML in a temporary file and notified to the gateway 11 using a signal that the processing is completed (26). Each application server 13 repeats this process as long as there is a request for an application server in the message queue 14. In the present invention, the monitor 12 and the application server 13 reside in a daemon format. When the result arrives from the monitor 12 and the application server 13, the gateway 11 grasps the result expressed in HTML or the multimedia data type, sets the MIME type by itself, and delivers the processing result along with the MIME type to the web server. (27).

Reference numeral 15 is a TCL file.

As such, the gateway according to the present invention integrates the web and the database in a complementary aspect. In order to connect the web and the database management system, the present invention basically supports the GET and POST methods of the HTML communication protocol and converts the database results through the gateway into HTML documents. It also provides the Web with data access rights constraints provided by database management systems, automatic data recovery, management of indexes and files, and the handling and security of complex data types.

In addition, the gateway according to the present invention provides gateway instructions for controlling the database and retrieving data. In other words, users can use the technologies of the Web to perform database functions such as building and updating database schemas, controlling transactions, managing classes, objects, methods, properties, indexes, users, data access rights, and executing queries. To make it work.

Table 1 summarizes the gateway commands according to the present invention.

Gateway commands can appear in HTML documents or URLs using HTTP's GET or POST methods. The following is an example of the format of a gateway command in a query string using the GET method.

function = functionname & arg1 = value1 & arg2 = value2 &…

http://marcia.etri.re.kr/cgi-bin/b3gateway?function = CreateClass & classname = new_class

Here, b3gateway represents a gateway (11 in FIG. 1) according to the present invention.

class CreatClass, DeleteClass, ConnectClass, DisconnectClass, SubclassCounter, GetSchemaCounter, GetsubclassName property AddAttribute, DeleteAttribute, UpdateAttributename, UpdateAttributetype, AttributeCounter, GetAttributename Method AddMethod, DeleteMethod, UpdateMethodname, UpdateMethodpath, MethodCounter, GetMethodname index CreatIndex, GetIndex, DeleteIndex, IndexCounter authority PrivilegeCounter, PutPrivilege, GetPrivilege, UpdatePrivilege Object AddObject, DleteObject, DeleteAllObject, GetObjectPoid, UpdateObject, ObjectsCounter, GetAttributevalue vaginal QueryResultcounter, GetQueryresult transaction TxBegin, TxCommit, TxRollback User management RegisterUser, DeleteUser, UserCounter, GetUsername, UpdatePassword

In this way, the URL is sent to the HTTP server running bada.etri.re.kr to send the data contained in the form of a query. In the query string, the CreateClass gateway command is displayed to request the creation of a new class (new_class).

The data conversion of the gateway according to the present invention will be described below.

Web client programs access data through many different servers. However, before sending data from the server to the client, the data must be able to be converted into an HTML document at the programmer's intent.

Referring to FIG. 1, the results of the database 16 are converted into HTML documents in the application server 13 of the gateway 10 according to the present invention. This data can be converted into a user-defined document type or a specific type. The present invention provides a database manager (DBA) command to support this conversion.

Database Manager (DBA) commands are for database management system operations, such as schema (), class (), object (), attribute (), method (), and query (). The execution result of the command is converted into the defined form of the HTML document. The following is an example.

http://marcia.etri.re.kr/cgi-bin/b3gateway?schema ()

By accessing the above URL using the GET method, the user can get information about the database schema. The application server executes schema () to retrieve the information and converts it to the specified form of the HTML document. The following shows the resulting document.

As described above, the present invention facilitates the modeling of complex data types and relationships between data by integrating the database management system and the web complementarily, and is effective for database recovery and data access authority management. In addition, it can support various types of platforms and user access using the web's hypermedia method. In addition, by adopting an application server method based on CGI, which is a standard server API method of all web servers, it is possible to reduce the burden caused by the development of the function of the web server and the HTTP communication protocol and to naturally connect with all existing web servers. It also has a small stub and daemon processor to relay the web server and database management system, and keeps the server and application of the database management system running all the time, waiting for the needs of the web server. In addition, the information provider can express the gateway method as intended, just as the information provider uses a CGI program.

Claims (3)

A gateway that sends a request from a client to a message queue and receives a result of the request to a web server; Create an application server by referring to the parameters related to the system environment, process transaction messages and broadcast messages among the messages transmitted from the gateway, notify the gateway of the results, and monitor abnormality of the application server to detect abnormal application servers. A monitor that you remove and replace with a new application server, And a web server including an application server for receiving and processing one message at a time for a message except for a transaction message and a broadcast message among messages transmitted from the gateway, and notifying the gateway of the result. Gateway structure for interworking database. The method of claim 1, The gateway is a structure of a gateway for interworking with the web and the database, characterized in that the database server command and the gateway command as shown in Table 2 to the application server. class CreatClass, DeleteClass, ConnectClass, DisconnectClass, SubclassCounter, GetSchemaCounter, GetsubclassName property AddAttribute, DeleteAttribute, UpdateAttributename, UpdateAttributetype, AttributeCounter, GetAttributename Method AddMethod, DeleteMethod, UpdateMethodname, UpdateMethodpath, MethodCounter, GetMethodname index CreatIndex, GetIndex, DeleteIndex, IndexCounter authority PrivilegeCounter, PutPrivilege, GetPrivilege, UpdatePrivilege Object AddObject, DleteObject, DeleteAllObject, GetObjectPoid, UpdateObject, ObjectsCounter, GetAttributevalue vaginal QueryResultcounter, GetQueryresult transaction TxBegin, TxCommit, TxRollback User management RegisterUser, DeleteUser, UserCounter, GetUsername, UpdatePassword A gateway receiving a database request from a web client, loading the request from the web client into a message queue; Receiving the client's request loaded in the message queue according to the type of monitor and application server; Analyzing the message received from the message queue and processing the message if the message loaded in the message queue is a transaction message or a broadcast message; Analyzing the message received from the message queue and processing a message other than a transaction message or a broadcast message by the application server; Storing the request processing result processed by the monitor and the application server in a file and notifying the gateway using a signal that the request processing is completed; And transmitting the request processing result to the web server at the gateway which has received the request processing result and the request processing completion signal from the monitor and the application server.